flush draws are easily in his range. not everyone bets out and if his aggression is low he isnt likely to be betting them out. im thinking that this is often a flush here, T9 is a good possibility as well. I cant really think of any hand other than those that he would raise the river with here. TP type hands likely just call, even AJ, two pair doesnt seem likely unless he has 87 and checked top pair...idk. tough spot.

actually, i think he might do this with 22, 44, and 88 as well. Do you see him taking this kind of line with a set? If we call i think its pretty much because we think he has 22, 44, and might be bluffing a bit here, but im more inclined to fold without further info.